MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



6. Transfer to a large dish of distilled water for three to five 

 minutes. 



7. Float sections onto slides; drain and carefully blot away- 

 excess water. 



8. Mount in glycerine jelly, Farrant or Aquamount. 



Note: Either ethylene or propylene glycol may be used; how- 

 ever, the former usually costs less than the latter. 



Reference: Chiffelle, T. L. and Putt, F. A., (195 1), Stain Tech., 26, 51-6. 



PROPYL ALCOHOL, NORMAL (OR ISO) 

 For dehydrating and clearing tissues prior to embedding 



Technique: 



1 . Pieces of fixed tissue are placed directly into normal propyl 

 alcohol and left therein overnight. 



2. Transfer directly into a bath of paraffin wax M.P. 40° C. 



3. After infiltration of the 40° C. wax, transfer to a bath of 

 52-54° C. paraffin wax for a few minutes; then cast the block. 



Note: This method prevents hardening and distortion of tissue : 

 it is particularly recommended for scirrhous carcinoma, connec- 

 tive tissue, tumours, etc. 



TERPINEOL 



For dehydrating sections 



Technique: 



1. After staining and before dehydrating, wipe the slides and 

 blot sections carefully, without allowing them to dry completely. 



2. Transfer to terpineol and agitate for a few seconds. 



3. Immerse in a second lot of terpineol for a few seconds. 



4. Drain and wipe the slides carefully. 



5. Clear with xylol, and mount as usual. 



Note: The destaining action of alcohol is avoided with this 

 method, which is harmless to the vast majority of stains. Neutral 

 Red being an exception. If desired, Cajeput Oil may be used for 

 clearing. 



38 



